Mount for crystal detectors.



. B. MILLER.

MOUNT 50H CRYSTAL DETECTORS.

APPLICATION FILED 1AN.2. 1917.

Patented Sept PATENT. oFFIo.

THOMAS B. MILLER, 0F SEATTLE, WASHINGTON, ASSIGN OR TO WIRELESS INSTRUMENT C0., 0F SEATTLE, WASHINGTON, A CORPORATION OF WASHINGTON.

MoUNr ron CRYSTAL .DETEcT'oRs Lava/,eea

` .new and useful Improvements in Mounts for Crystal Detectors,^of which the following is a specification.

My invention relates .to detectors for use which are known as crystal detectors.

The object of my invention 'is to produce a vdetector of this' type which is of rugged and reliable construction, not likely to be deranged-and its operation interfered with by jars, concussioris, or other rough treatment,

one which may be easily adjusted to place claims.

its contact member at any point upon the surface of the crystal, in which the crystal and its complemental contact members are inclosed and not subject to outside influences and in' which, once a satisfactory contact is obtained, this may be retained.

My invention comprises the peculiar and novel constructions which are involved in the device and which will be hereinafter shown and then' particularly defined by the In the accompanying drawings I have shown the type of construction which .is now most preferred by'me, although aware that this construction may be considerably varied 4without essentially departing from 4the principles upon Which my invention is based.

Figure 1 1s a plan View of my device with the top portion removed.

Fig.` 2 is an insideplan view with said a'mcdiied typey of construction.

Fig. 5 is a plan view of this modified construction..

In 'the use of crystal detectors, that is,-

the detectors of the type in -which a fine point is placed incontact withk a mineral,

`usually la natural crystal, good results are obtained when a proper contact can `be maintained. However, it is diiiicult to obtainand maintain a proper contact upon specification f Letters Patent.

in radio signaling and consists in an im-v proved construction of the type of detectors Patented sept. 3, 1918.

Application led January 2, 1917. y Serial No. 140,243.

the crystal and for this reason detectors of this kindv are loften lunsatisfactory. Such detectors quite generally have the 'crystal and the contact. point exposed to dust and atmospheric infiuences,=4 and furthermore,

means are not usually provided whereby adjustment may be had to any surface of the c stal. Furt er, when such' adjustment is o tained, that is found to Work well, the permanence .of this condition cannot be obtamed with certainty. In constructing my device, I employ'a base member 1 W ich has a cylindrical shell lpoint upon the 10, forming a casing within which the operating parts are mounted. In the construction shown in Figs. 1, 2 and 3, the base 1 and the shell 10, which form the casing proper, are made as'separate pieces, being secured by any suitable means, as by screws. In the construction shown :inF ig. 4, these two parts are integral with each other.

In the type of construction shown in Figs. 1, 2 and 3, I mount a contact point upon the base 1 andthe crystal upon the case l0, the crystal in this case being mounted so as to be rotatable and the contact oint being mounted for movement in a pat which extends from a point which substantially coincides with the axis of the rotation of the crystal outwardly to a point which extends substantially to the outer limits of the crys tal. The crystal 2 is mounted in a holder 20, as by being embedded-within a mass of `cement 21, contained inthe hollow of the holder 20. The holder 20 is mounted to be turned about an axis. The manner of doing this, shown in Fig. 3, consists in providing the cup 20, which forms the holder with a stem 22. which is secured into a boss of a metal plate 23. This boss forms a neck 9 which has a bearing in a plate 24: which is secured to the casing 1Q. `The'casing 10 should preferably be of an insulating material lor in so1n other manner the crystal holder should be linsulated from the other parts.

TheV plate 23 is also provided with a knob Aor cap 25 forengagement with the hand so that the crystal may be turned into any angular position deslred. As a means for holding the crystal holder in any adjusted position, I have inserted a spring washer 26 between the holder 20 and the inner surfaces .of the This will provide su plate 24 upon which it is turned. fic'ient frictional reiVithin a recess in the base 1 is placed a lever 3, which lever lis pivoted at 30, and

' other met-al.

at its opposite end is provided with means by which it may be swung upon its pivot. Said means may be of various constructions. The construction herein shown 'consists in providing a swinging end of the lever 3 with a slot 3l which receives a pin 32 carried by` a lever 4, which lever is pivot-ed at -a convenient point within the casing, as 40, and has its swinging end extending without the casing, being at this end provided with a knob 4l, or any other construction by which it may be conveniently manipulated.'- The sect-ion l0 of the casing is provided with la recess section 1l vof such extent as to accommodate the swing of the lever d. The lever 3 is provided with a spring plate 33 secured by its base to the lever and carrying the contact point 34, which made ot steel or In this manner the contact point is yieldingly supported so that it will be able to maintain Contact with the face of the crystal, irrespective of whether the piece of this crystal is or 1s not a close approxi.- mate ot' a plane. The triangular shape ot the spring member 33 secures rigidity lof the support against movement of the said support and the lever 3, while making it easily yielding in a direction perpendicular to this plane.

lThe pivot 30 is employed as one lead. The other lead consists of the screw by which the spring contact bar 5 is supported. rihis spring Contact bar is curved so as to fit against the outer surface of the crystal holder Q0. ln this manner electrical contact is made with the crystal. By swinging the lever '-l to one side or the other the ,contact point may be moved from y a position which coincides with the axis by turning the crystal to a point extending to the extreme outer part ot the crystal holder. This movey ment, combined with the rotation ot' the crystal, makes it possible to4 utilize the envtire surface ot the crystal for contact with the contact point 4;. f In the construction shown in Figs. LFand 5 the crystal holder,'or cup 20, is mounted with the base l.

In this case the vcrystal holder is not rotatable. .34 is upon the end .of an arm 35 which has la pivot section 36 extending through the cap member 6, which cap member ismounted to -rotate in a, plate 7 which is secured to the outerv part of the casing 10. The ,casing 10 should be of an insulating material, while the plate 7 and the portionG of the rotatable cap should be of metal or conducting 'ma-- terial. `In this case, a lead wire passes through the body of the casing and con- 7. The rotative member 6 is provided with a knob 60, secured `1naterial, andhaving a recess (il in lThe contact point "hereto, by which it may be' turned, said knob being preferably of noncon'ducting its outer surface in which is placed a -finger (i2, which is secured to the aXis portion 36 of the contact member.

A scale 63 may be made upon the knob 60, which, with the pointer G2, may be used to give an indication as to the position of the contact point 34. The axis, upon which this contact point turns, is placed eccentric to the aXis of turning ot' the member (i. The length of the arm 35 is such that the contact point may be made to swing over a pat which extends from the axis of rotation outwardly. This, together with the rotation of the member which carries this contact'arm,

-vill enable bringing the contact point in contact with any point upon the face of the crystal.

By the constructions herein illustrated, the crystal and the member which contacts therewith, are placed within .an inclosed case where they are not affected by dust, dirt, and atmospheric conditions. Further, it is possible to easily adjust the device so as t0 obtain the Contact otany point upon the crystal.' Further, the points are so constructed that 'when once adjusted'in favorable condition, this adjustment may be maintained. By reason of this, one 'of the chief objections of the crystal detector is obviated. Also, by reason of these same facts, jarring or shaking oi this detector prevents dearrangement of the adjustment. I have found by experience that this detector will maintain its adjustment even when violently, jai-red. What I claim my invention is:

l. A mount for a crystal detector comprising a closed casing and a rotatable closure therefor, a crystal mounted upon one ot said parts within the casing and a contact arm eccentrically pivoted upon the other, and means for swinging said arm.

2. A mountfor aA crystal detector 'comprising a casing, a rotatable closure therefor, a crystal carried by one of said parts within the casing and a eccentrically pivoted upon the other part tu carry its point over a path extending from a central position outward, and means eX- tending without the casing yfor adjusting said point.

3. AA mountor a crystal detector comprising a casing, a rotatable closure therefor having a crystal holder Within the Jcasing, an arm eccentrically pivoted Within "the casing, a contact point yieldingly carried by said arm and movable by the swinging ot said arm from a central position outwardly, and-means for swinging said arm from without the casing.

LPA mount for a crystal detector comprising a casing, a rotatable closure there- 5 said arm from a central position outwardly,

a pivoted controlling lever having actuating enga-gement with the first named lever and extending to withoutthe casing.

5. A mount for a crystal detector coinm prising a casing, arotatable closure therefor having a conductive crystal holder lwithin the casing, a yielding conductor carried by the casing and engaging the crystal holder,

a lead extending from said conductor to without the casing, a 'second lead extending within the casing, a lever eccentrically piv- 'oted within the casing and connected with said second lead, a contact member carried by said lever and 'adapted to engage the crystal, said point of engagement being movable by the swing of said lever from a central position outwardly, and means for swinging said lever from without the casing.

Signed at Seattle, Washington, this 23rd .day of December, 1916.

THQMAS B. MILLER; 

